This invention relates generally to sound activated devices, and more particularly to such a device which is activated in response to the audible signal from an alarm.
The use of smoke and fire detectors in homes and apartments have become increasingly common and, in some locales, are required to meet building codes for new home and apartment construction. Very often, several of these detectors are provided throughout a home or apartment. When fire or smoke is detected, the device emits a relatively loud alarm for warning the occupants of the residence of the existence of the fire or smoke. If the occupants are sleeping, the alarm is sufficiently loud and harsh to alert the persons to the danger.
In the event that the fire has progressed, it is likely that the lights powered by the main electrical system of a residence will be inoperative. The residence may be filled with an appreciable quantity of smoke so that the occupants may become disoriented and find it difficult to escape from the dark, smoke filled area. The darkness problem created by smoke will be compounded if the fire occurs during the evening hours.
Emergency escape lights that automatically turn on in the event of an alarm condition exist in the prior art. Many of the prior art lights are integrally designed into smoke or fire detecting units or are physically wired to a fire alarm or smoke detecting system. Others of the escape lights are self contained. A self contained light will turn on when a loud sound occurs within a predetermined frequency range. However, many loud noises occur within the predetermined frequency range other than the sound generated by the alarm. For example, radio, television and vacuum cleaner noises are generally within the same frequency range as is the sound generated by the alarm. Since such prior art lights are designed to be activated when the frequency of an audible noise is within a predetermined range, the light is often activated when its illumination is not actually required.
Other alarm attention directing devices, such as alarms, sirens, warning lights and the like can also be designed to be activated in response to the occurrence of noise within a predetermined frequency range as generated by a smoke alarm. It is likewise desirable that these other devices only be activated in response to the sound emitted from the smoke alarm and not be activated by sound emitted from another source.
Accordingly, it is an object of the present invention to provide a sound activated device which is automatically activated in response to its detection of sound having specific informational characteristics. It is a further object of this invention to activate a sound activated device in response to a digital signal having specific characteristics.